Fire-door casing for furnaces



(No Modem J. R. MOELLIGOTT.

FIRE DOOR GASING FOR FURNAGES. No. 325,105. Patented Aug. 25, 1885.

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UNITED STATES PATENT OFFICE.

JAMES R. MCELLIGOTT, OF CHICAGO, ILLINOIS.

FIRE-DOOR CASING FOR FURNACE-S.

SPECIFICATION forming part of Letters Patent No. 325,105, dated August 25, 1885.

Application tiled June 6, 1885. (No model.)

To all whom it may concern:

Be it known that I, JAMES R. MGELLI- GOTT, a citizen of the United States, and a resident of the city of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Fire- Door Gasings for Boilers,Furnaees, and the Like, of which the following, when taken in connection with the drawings accompanying the same and forming a part hereof, is a full and complete specification.

The object of my invention is mainly to secure a casing for the lire-doors of boilers and furnaces which will not burn or be burned out when an intense heat is attained in the lire-box of the boiler or furnace, and also to provide means whereby heated air or air and steam may be supplied the fire-box above the surface of the fire therein. i

I have illustrated my invention as applied to an ordinary boiler.

Figure l is a sectional view on line l l of Fig. 2. Fig. 2 is a sectional view on line 2 2 of Fig. 1. Fig. 3 is a perspective view of one ot' the sides of my improved casing, with a portion of one face broken away to show the interior thereof. Fig. 4 is a perspective view of the bottom plate of my improved tiredoor casing, with a portion of the same broken away, showing the interior thereof. Fig. 5 is a plan view ot' pipes D and D.

Like letters referto like parts throughout the several views.

W is the grate of the tire-box. X is the boiler. Y is the re-door. A is the bottom plate of the casing. A is the top plate. B B are the side plates. D is apipe having branches D D. E E are lugs or projections on the inner surface of the top and bottom plates. F is a hollow space, forming an airchamber in the top and bottom plates. F is a hollow space forming an air-chamber in the side plates. a ci are holes drilled or cast in plates A A. b b are holes drilled or cast in plates B B. e e are holes drilled or cast in top plate, A.

The several plates used by me and illus trated by the drawings are each formed of an outer and inner wall, thus securing 'an airehamber therein, and are provided with holes, cast or drilled therein, by which air is admitted into the air-chamber formed in 'the therefrom throughout the whole casing..

Plates B B and A also contain holes b b and e c, through which air is admitted into the lire-box. Steam from the boiler is forced through pipe D and branches D D and through holes c e.

The manner in which my improved casing is constructed is as follows: Bottom plate, A, is placed over the ash-door, and set in brick or metal in such mamer that air may enter through holes a a on the bottom face or wall of said plate and circulate freely in and around the airehamber formed between the outer and inner wall of said plate. Side plates, B B, are set on bottom plate, A, and over holes ay a therein, pressing against lugs E E, and the brick facing ordinarilyemployed for the front of the tire-box is laid against the outer face of the outer wall of said plate B. Top plate, A, is then laid upon the upper edges ot' side plate, B B, and one or more courses of brick may be laid upon said top plate, A. I prefer to so place plate Al that but one course ot' brick shall rest upon the same between it and boiler X.

The manner in which my improved lire-door casin g operates is Air is admitted into cham ber F of lower plate, A, through holes a a in the lower wall thertot', and circulates more or less freely through and around said chamber F, and from said chamber passes through holes aa in the upper wall of said lower plate, A, into and around air-chamber F of side plates, B B. From airchamber F the air passes through holes a a in lower wall of top pla-te, A, in and around air-chamber F in said top plate, and air in said chamber F also passes through holes b b in plate B directly into the fire-box. Air in chamber F of upper plate, A, passes through holes c e in the side wall of said top plate directly into the fire-box. As the air contained in said air-chambers F and F becomes heated, it passes into the fireboX through holes b b and holes c c, a constant current of air being induced thereby. This action, being greatly accelerated by thc draft of the lire-box and the current of air being thus supplied being at a high temperature, greatly assists in the perfect combustion of the gases in the fire-box. In order that the supply of air thus heated and admitted into the fire-box may bc increased, if desired,

by forcing steam through holes c c in top plate, A', thus increasing,1 to a still greater degree the incidental or minor object of my inven-V tion, it is necessary merely that pipe D, with branches D' D', be placed'in air chamber F ot' top plate, A'. Pipe D is connected with the boiler X. Pipes D' D' are of smaller outside diameter than is the inside diameter of holes e e, and stop j ust in front of or project a very little Way into said holes e e. It', now, steam be admitted to pipe D and branches D' from the boiler, a very stron g blast of heated air and superheated steam or steam enters the tire-box through said holes e e.

I am aware that Various methods have been provided for supplying' air or air and steam lo the rebox of a boiler or furnace over the re therein, and I do not therefore claim this,

broadly, as my invention, the main object of my invention being to secure a casin for liredoors of boilers and furnaces which will not burn or be burned out; and

Vhat I claim, and desire to secure by lietters Patent, is-

l. A casing` for 'tiredoors in boilers and furnaces, consisting of a hollow plate, forming thebottom oi'said casing, in combination With hollow side plates and a hollow top plate, all said plates having holes permitting the admission and circulation of-air in said casing, said side and top plate also havin g holes into said iirebox, all substantially as described, and i'or the purpose set forth.

2. A casing for iireedoors in boilers and furnaces, consisting of hollow plate A, having,` holes a a. therein, side plates, B, having holes b b therein, and top pla-te, A', havin g holes a a and e e therein, all combined substantially as described, and for the purpose specified.

3. A casing1 for iiredoors in boilers and furnaces, consistingot hollow plates A A' and B B, having holes a a., b b, and c e therein, in combination with pipe D, haring;` branches D D', all substantially as described, and for the purpose specified.

JAMES R. MCELLIGOTT.

Witnesses CHARLES T. BROWN, FLORA L. BROWN. 

